Fuel Tank Drain Plugs

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lifefloat
United States of America
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Fuel Tank Drain Plugs

Post by lifefloat »

Does any one have a special way they have discovered to remove the drain plugs from the fuel tank?

I do not wish to drop the tanks at this time (712 dual tanks) as I like a running vehicle during hurricane season. I think I'd be in for a few days of down time if I dropped them. Unless I'm wrong? Estimated time to drop and reinstall?

Anyway..................I just want to remove the drain plugs right now. They are frozen in place. I've been hitting them with myriad different break-free sprays.... not budging. Losing the hex on one of them. Vice grips can't get enough grip on thin edge.

Drilling them out just seems like a really bad idea. Or using a torch. haha..........

I'm open for suggestions or if anybody can guesstimate drop and reinstall time and likely parts to replace after a drop and reinstall so I can keep down time to a minimum.............
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rmel
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Re: Fuel Tank Drain Plugs

Post by rmel »

Find a socket the same diameter as the drain plug, place the flat side up against the
plug and give it a good wallop. Might help to break it free, and might not. Penetrating
oil won't help.
Puller: 71' 710K 2.7L EFI aka Mozo
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ChickenPinz
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Re: Fuel Tank Drain Plugs

Post by ChickenPinz »

I leaned on mine pretty hard to break it free, but it wouldn't budge so I deferred that project.

Thinking now, I might try cold spray (AKA: Freon) to chill it to try to break the copper sealing ring bond. You could go the other way also, of heating it, but given that it's a fuel tank that might be riskier (YMMV).
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ChickenPinz
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Re: Fuel Tank Drain Plugs

Post by ChickenPinz »

I leaned on mine pretty hard to break it free, but it wouldn't budge so I deferred that project.

Thinking now, I might try cold spray (AKA: Freon) to chill it to try to break the copper sealing ring bond. You could go the other way also, of heating it, but given that it's a fuel tank that might be riskier (YMMV).
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lifefloat
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Re: Fuel Tank Drain Plugs

Post by lifefloat »

So..................I'll try giving it a wallop with a socket flat..........and yeah....obviously the penetrating oil isn't doing anything.

I like the freeze idea as well...........never thought of that. It can't hurt.

Once again..............any idea of estimated labor time in dropping the tanks? Couple/three hours? Probably gonna be more like dammit all day project.

I wish I had a garage. I do all of my work in the dirt. O well. Builds character. And makes it more of a real world repair scenario. :D
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rmel
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Re: Fuel Tank Drain Plugs

Post by rmel »

Depends on why you want to drop the tanks. Taking them down
and putting them back up is about an hour job (each). But I presume
your going after a problem, which might be the gating item.

From my own experience, I had dropped my tank to gussy it up with
a paint job but then noticed symptoms of Read Death at the bottom
of the tank. Four days later it was back in with a new lining and paint job.

Sometimes there are surprises to content with :?
Puller: 71' 710K 2.7L EFI aka Mozo
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ChickenPinz
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Re: Fuel Tank Drain Plugs

Post by ChickenPinz »

lifefloat wrote: Wed Sep 01, 2021 4:56 am I wish I had a garage. I do all of my work in the dirt. O well. Builds character. And makes it more of a real world repair scenario. :D
I feel your pain, sir. All my work is on gravel. I think of it as a free back massage, and it does turn me into a hoarder of large sheets of cardboard.

Oh, and your best friend? A powerful magnet to find those dropped fasteners that perfectly blend in with the dirt/rocks/weeds/sticks/leaves...
Last edited by ChickenPinz on Mon Sep 06, 2021 6:45 pm, edited 1 time in total.
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pinzinator
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Re: Fuel Tank Drain Plugs

Post by pinzinator »

Soak with P-Blaster for a few days and it should break loose.
I ran my Pinz low on gas last month and then drained the tank, this is regular maintenance. I'm care not to overtighten the drain plug, along with the rest of them on the vehicle.
gorsko
Bulgaria
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Re: Fuel Tank Drain Plugs

Post by gorsko »

Had the same issue - tank half-full of very stale fuel which I wanted to drain completely, & after trying various approaches with products & force, eventually resorted to lengthy application of heat from a hot-air gun (I know...not ideal) followed by a well-placed hammer blow. Came free easily then!
Threads heavily rusted, guessing from water absorbed by the fuel sitting at the bottom of the tank. Now replaced with a nice new plug & copper washer...
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JimmyC
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Re: Fuel Tank Drain Plugs

Post by JimmyC »

I doubt if penetrating solvent will do much good as the threads are on opposite side of the seal ring. Can you get a pipe wrench on it?
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ChickenPinz
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Re: Fuel Tank Drain Plugs

Post by ChickenPinz »

pinzinator wrote: Sun Sep 05, 2021 8:13 pm Soak with P-Blaster for a few days and it should break loose.
I ran my Pinz low on gas last month and then drained the tank, this is regular maintenance. I'm care not to overtighten the drain plug, along with the rest of them on the vehicle.
How low (by the gauge) do you run it before draining, and how much fuel do you get out?

<more data for my fuel gauge calibration exercise>
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